Project Summary/Abstract Families headed by sexual and gender minorities are a growing segment of the population, yet sexual and gender minority health disparities in areas including self-rated health, chronic conditions, health behaviors, and depression persist. Minority stress has been implicated as a key cause of health problems, and family functioning, emotion regulation, couple-level minority stress, and community contexts have been identified as potential mechanisms underlying these associations. Contemporary theoretical models have yet to be tested due to a lack of data, and further, this lack of data has made studies of the intersection of racial and ethnic minority stress with sexual and gender minority stress difficult. This project will produce the first population- representative, multi-method, fully-powered study of cohabiting and married sexual and gender minorities and their partners, and a comparison sample of cis-gender individuals in different-gender unions. Aim 1. Evaluate whether and how family functioning (e.g. relationship quality) mediates the negative effects of stress due to discrimination on physical and mental health and health behaviors. Aim 2. Using an experience sampling method embedded in a time-diary, examine 1) the mediating role of emotion regulation, and 2) dyadic stress processes in the association between stress and subsequent health behaviors and time-use among same- gender couples. Aim 3. Investigate the association between community-level factors including economic disadvantage, access to healthcare, and the sexual and gender minority political climate (i.e. state employment protections) and sexual and gender minorities? physical and mental health and health behaviors. Aim 4. Determine race and ethnic health gaps among sexual [and gender] minorities and evaluate potential protective factors that may minimize these gaps. We will recruit 2690 US adults aged 18 to 60 who are cohabiting or married to same- and different-gender partners, along with their partners. The sample will include an oversample of respondents of color. Population-representative Gallup samples afford a unique and efficient opportunity to study sexual and gender minorities who are in unions via targeted sampling. Using a mobile phone application platform, we will also collect time-diary and experience sampling method data. The primary significance of this project is 1) the identification of family functioning and emotion regulation as mediators of sexual and gender minority stress due to stigma and discrimination and poor physical and psychological health and health behaviors, and 2) the collection of dyadic data that will elucidate dyadic minority stress processes. The proposed research is innovative because it is the first contemporary, population-representative study of sexual and gender minority health that includes family functioning, emotion regulation, and dyadic data and an oversample of racial and ethnic minorities. These data will help researchers better understand how to improve the health of sexual and gender minorities by illuminating potential mechanisms underlying health disparities. Data will be available to scholars across the world through ICPSR and the American Heritage Time Use Study.